
Generation of optical OFDM signals using 214 GS/s real time digital signal processing
Author(s) -
Y. Benlachtar,
Philip M. Watts,
Rachid Bouziane,
Peter Milder,
Deepak Rangaraj,
Anthony Cartolano,
Robert Koutsoyannis,
James C. Hoe,
Markus Püschel,
Madeleine Glick,
Robert I. Killey
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.017658
Subject(s) - orthogonal frequency division multiplexing , computer science , electronic engineering , transmitter , fast fourier transform , signal (programming language) , digital signal processing , multiplexing , signal processing , bit error rate , computer hardware , telecommunications , engineering , channel (broadcasting) , algorithm , programming language
We demonstrate a field programmable gate array (FPGA) based optical orthogonal frequency division multiplexing (OFDM) transmitter implementing real time digital signal processing at a sample rate of 21.4 GS/s. The QPSK-OFDM signal is generated using an 8 bit, 128 point inverse fast Fourier transform (IFFT) core, performing one transform per clock cycle at a clock speed of 167.2 MHz and can be deployed with either a direct-detection or a coherent receiver. The hardware design and the main digital signal processing functions are described, and we show that the main performance limitation is due to the low (4-bit) resolution of the digital-to-analog converter (DAC) and the 8-bit resolution of the IFFT core used. We analyze the back-to-back performance of the transmitter generating an 8.36 Gb/s optical single sideband (SSB) OFDM signal using digital up-conversion, suitable for direct-detection. Additionally, we use the device to transmit 8.36 Gb/s SSB OFDM signals over 200 km of uncompensated standard single mode fiber achieving an overall BER<10(-3).